In the display field, Liquid Crystal Display (LCD), Organic Light Emitting Diode (OLED) and other panel display devices have been gradually replaced the Cathode Ray Tube (CRT) displays.
The OLED display possesses many outstanding properties of self-illumination, low driving voltage, high luminescence efficiency, fast response, high clarity and contrast, near 180° view angle, wide range of working temperature, applicability of flexible display and large scale full color display. The OLED is considered as the most potential flat panel display technology.
With the development of the display technology, there has been a TOC (Transistor On Color Filter) type OLED display, in which a thin-film transistor (TFT) driving circuit is provided on a color filter (CF). The polarizer can be eliminated in the TOC type OLED display, which can make the OLED display element thinner and the manufacture cost is lower.
The manufacturing process of the TOC type OLED display comprises:
first, preparing CF on the substrate;
then, preparing TFTs on the color filter layer.
Since the color filters (CF) is prepared first, the following preparation of TFT must be conducted in a condition that a temperature is less than 230 Celsius degrees.
Besides, the conventional TOC type OLED display generally uses a material, such as indium (In), gallium (Ga) and other expensive rare metal materials to fabricate a channel layer of a TFT. Although the electrical performance of the TFT can be improved, the production cost needs to be further reduced.